Superlux HA3D headphone amplifier review

December 10, 2010

Taiwanese brand Superlux continues to introduce products that upsets the pricing standard of professional audio products. Not stopping with the HD668B monitoring headphone that we’ve reviewed a while ago, they’ve continued their invasion into microphones, portable headphones, and now, headphone amplifiers.

The HA-3D headphone amplifier clearly was designed for the professional audio and television production crowd. It has a tank-like build quality, pro-style 1/4″ connectors, balanced line inputs, 1/4″ TRS stereo inputs and loop outs. The dimension of the amp is fairly big by today’s standard of RSA-Shadow and Pico-Slim sized amps. You certainly won’t be taking HA-3D amp during day to day activities. Despite the “professional irregularities”, the HA-3D amplifier offers quite some interesting features that makes us decide it’s worth writing an article on.

The first and most striking feature is how the amplifier is able to drive three headphones simultaneously, while offering individual volume control for each headphone! Yes, three separate, isolated headphone amplifier circuits in one box! It’s not something that the average people would need everyday, and yet, it still is highly fascinating because now you’re suddenly able to burn three headphones simultaneously without much problems. Or, you can share your music with friends without having to fight over the volume control. Or, being the headphone addicts that we are, you may want to A-B headphones and the HA-3D will let you A-B-C headphones and volume-matching the three headphones easily.

Considering that the HA-3D runs only on two AA batteries, it’s pretty surprising how the amplifier is able to drive full size headphones simultaneously without breaking a sweat. The amplifier circuitry runs on +-15V, and it’s quite potent to drive big full size headphones to ear-shattering levels. I’m talking headphones like the Sennheiser HD600, HD650, HD800, and the LCD-2 grade here, not some easy to drive Audio Technicas. Yes, three big full size headphones running on full volume with only two AA batteries! This amp wowed everyone during our last local gathering, as everybody was happily listening to three headphones simultaneously blasting music from the same source. The only headphone that I’ve found the HA-3D to be incapable of driving properly is the Hifiman HE-6 (and perhaps the HE-5 variants as well), but the LCD-2 is quite a light drive for the HA-3D (9-10 O’clock with the LCD-2). Superlux claims 8 hours of battery life out of the 2x AA internal batteries. Nothing grand there, but what can you expect from 2x AA batteries? At least I can see that they’re aiming for easy availability of batteries when people are using it for on-location production sessions. If you have AC power available, the HA-3D also takes an external power supply in the range of 5V to 17V. I wonder if you can make it run on USB power with the cable.

Other notable features of the HA-3D is the loop out, which will allow you to pass on the signal to another HA-3D unit for six simultaneous headphones running at the same time with six individual volume controls. The lack of RCA input is probably not a very good thing with the audio crowd, but using an Ipod, I can use a typical LOD cable and plug it in the 1/8″ input jack. For IEM users, the first headphone output offers a choice between 1/8″ and 1/4″ TRS jacks. The monstrous gain is not very ideal for IEMs though, as the range for volume control is very limited, and there’s always some channel imbalance problems on analog potentiometers in low volume settings. But if you can live with the non-ideal volume control, you can definitely listen to some IEMS through the amps, even sensitive ones such as the JH16Pro.

The sound quality is actually very good for something that is at this price range (and with so many features as well). It’s not going to start taking businesses away from HeadAmp and the such, but the HA-3D has quite a clear sound without no noticeable distortions. Obviously, the pro-crowd isn’t going to take use anything that has any forms of distortions. The sound does have one flaw though, that is the recessed midrange. Midrange is quite clear, but it doesn’t have enough presence and body for general music listening with vocals. So that’s going to be one of the catch with this otherwise great sounding amp. With Electronics and Classical, I don’t see the midrange to be a big problem, and the straightforward, dynamic, and lively sound of the HA-3D turns out to be quite fun sounding.

Gears used for review:

Headphones: Sennheiser HD600, HD650, HD800, Audez’e LCD-2, JH16Pro

Source: HRT Music Streamer II+, Ipod Classic 120GB